Objective and Subjective Characteristics of Sleep after Coronary Artery Bypass Graft Surgery in the Early Period: A Prospective Study with Healthy Subjects

Abstract

The purpose of this study was to investigate changes in sleep characteristics by examining both subjective tests and objective parameters such as actigraphic sleep analysis in patients who underwent coronary artery bypass graft surgery (CABG). Forty-five patients who underwent CABG operations and did not have any sleep disturbance were examined. They were evaluated by subjective and objective sleep parameters at the beginning of the examination and on the fifth postoperative day. Forty healthy subjects who did not undergo the operation were also evaluated. The Pittsburgh Index and Epworth values in the postoperative group were significantly higher, but Maintenance of Wakefulness Test lengths were significantly shorter than in the preoperative and control groups. Sleep latency, napping episodes, total napping periods, and fragmentation index values of the postoperative group were significantly higher, but sleep efficiency values were significantly lower than in the preoperative and control groups. The cause of sleeplessness after CABG surgery may be the temporary deterioration of circulation in the centers of the brain stem and hypothalamus, which control sleep and awakening. It can be proposed that the improvement of the circulation in these centers a couple of months after the operation help to regain sleep control, and thus sleep disturbances disappear.